Occasionally, someone claims to have built a perpetual motion machine that can generate energy indefinitely from nothing. For this discussion topic, address the following.

1. Why are perpetual motion machines impossible according to the laws of physics? In particular, how do perpetual motion machines violate the laws of thermodynamics?
2. Research and find one of the perpetual motion machines constructed (or designed) by a past inventor or scientist. Discuss why this machine will eventually run down. Include a picture, illustration, or video.
3. NASA has made news in recent years due to its development of the controversial EmDrive, an "impossible" engine that could make interstellar travel possible. Address the implications of this drive and why it should, in theory, not work according to the principles forbidding the operation of perpetual motion machines. Give your opinion on whether the EmDrive is a real operating engine.